The signal intensity of phase-conjugation-type delayed-time four-wave mixing (TDFWM) with incoherent light is studied based on the two-level broad band model of semiconductor optical amplifier (SOA). The theoretical results show that the signal intensity not only decays with the dephasing rate of SOA but also pulsates with the delay time. Since the experimental investigation of both the carrier pulsation and the dephasing time using degenerate four wave mixing are limited only in the application cases of high-power laser, large optical experimental platform and sophisticated detection devices at present, a novel scheme composed of all-optical communication devices is proposed based on non-degenerate four-wave mixing. This means that both pump wavelength and probe wavelength not only are easily selected but also an experimental setup can be minimized.